The atmosphere is what makes it possiblelife on earth. We receive the very first information and facts about the atmosphere in elementary school. In high school, we have already become more familiar with this concept in geography lessons.
The concept of the earth's atmosphere
The atmosphere is present not only on Earth, but also onother celestial bodies. So called gas envelope surrounding the planet. The composition of this gas layer of different planets is significantly different. Let's look at the basic information and facts about the atmosphere of the Earth, otherwise called air.

Its most important component isoxygen. Some people mistakenly think that the earth’s atmosphere consists entirely of oxygen, but in reality air is a mixture of gases. It is composed of 78% nitrogen and 21% oxygen. The remaining one percent includes ozone, argon, carbon dioxide, water vapor. Let the percentage ratio of these gases is small, but they perform an important function - they absorb a significant portion of the solar radiant energy, thereby preventing the sun from turning all life on our planet into ashes. Atmospheric properties vary with altitude. For example, at an altitude of 65 km, nitrogen is 86%, and oxygen is 19%.
The composition of the Earth’s atmosphere
- Carbon dioxide necessary for plant nutrition.In the atmosphere it appears as a result of the process of respiration of living organisms, decay, burning. Its absence in the composition of the atmosphere would make the existence of any plants impossible.
- Oxygen - vital for human component of the atmosphere. Its presence is a condition for the existence of all living organisms. It is about 20% of the total volume of atmospheric gases.
- Ozone - it is a natural absorber of solarultraviolet radiation, which adversely affects living organisms. Most of it forms a separate layer of the atmosphere - the ozone screen. Recently, human activity leads to the fact that the ozone layer begins to gradually deteriorate, but since it is of great importance, it is actively working to preserve and restore it.
- Water vapor determines the humidity of the air.Its content may vary depending on various factors: air temperature, location, season. At low temperature, water vapor in the air is very small, maybe less than one percent, and at high temperatures it reaches 4%.
- In addition to all of the above, a certain percentage is always present in the composition of the earth's atmosphere. solid and liquid impurities. These are soot, ash, sea salt, dust, water droplets, microorganisms. They can get into the air both naturally and anthropogenically.

Atmosphere layers
И температура, и плотность, и качественный состав air is not the same at different heights. Because of this, it is customary to isolate different layers of the atmosphere. Each of them has its own characteristic. Let's find out which layers of the atmosphere are distinguished:
- Troposphere - this layer of the atmosphere is closerjust to the surface of the earth. Its height is 8–10 km above the poles and 16–18 km in the tropics. Here, 90% of the total water vapor that is present in the atmosphere is located; therefore, active cloud formation occurs. Also in this layer are observed such processes as the movement of air (wind), turbulence, convection. The temperature ranges from +45 degrees at noon during the warm season in the tropics to -65 degrees at the poles.
- Stratosphere - the second most distant from the earthsurface layer of the atmosphere. It is located at an altitude of 11 to 50 km. In the lower layer of the stratosphere, the temperature is approximately -55, in the direction of distance from the Earth, it rises to + 1 ° C. This area is called inversion and is the boundary of the stratosphere and mesosphere.
- The mesosphere is located at an altitude of 50 to 90 km.The temperature at its lower boundary is about 0, at the top it reaches -80 ...- 90 ˚С. Meteorites that enter the atmosphere of the Earth completely burn in the mesosphere, because of this, the air is glowing.
- The thermosphere is approximately 700 km thick.In this layer of the atmosphere auroras appear. They appear due to the ionization of air under the action of cosmic radiation and radiation emanating from the sun.
- The exosphere is a zone of air dispersion. Here, the concentration of gases is small and their gradual departure into the interplanetary space takes place.

The boundary between the earth's atmosphere and space expanses is considered to be the milestone of 100 km. This feature is called the Pocket line.
Atmospheric pressure
Listening to the weather forecast, we often hear indicators of atmospheric pressure. But what does atmospheric pressure mean, and how can this affect us?
We figured out that air is made of gases andimpurities. Each of these components has its own weight, which means that the atmosphere is not weightless, as it was believed until the XVII century. Atmospheric pressure is the force with which all layers of the atmosphere press on the surface of the Earth and on all objects.
Scientists have made difficult calculations and proved thatper one square meter of space, the atmosphere presses with a force of 10,333 kg. This means that the human body is subject to air pressure, which weighs 12–15 tons. Why do we not feel this? It saves us its internal pressure, which balances the external. You can feel the pressure of the atmosphere, while in the plane or high in the mountains, as the atmospheric pressure at a height is much less. At the same time physical discomfort, laying of ears, dizziness is possible.
Interesting information and facts

There is much to say about the atmosphere surrounding the globe. We know a lot of interesting facts about her, and some of them may seem surprising:
- The weight of the earth's atmosphere is 5 300 000 000 000 000 000 tons.
- It contributes to the transmission of sound. At an altitude of more than 100 km, this property disappears due to a change in the composition of the atmosphere.
- The movement of the atmosphere is provoked by the uneven heating of the Earth’s surface.
- A thermometer is used to determine the air temperature, and a barometer is used to find out the pressure force of the atmosphere.
- The presence of the atmosphere saves our planet from 100 tons of meteorites daily.
- The composition of the air was fixed several hundred million years, but began to change with the onset of rapid industrial activity.
- It is believed that the atmosphere extends up to an altitude of 3000 km.

The value of the atmosphere for humans
The physiological zone of the atmosphere is 5 km.At an altitude of 5000 m above sea level, a person begins to show oxygen starvation, which is reflected in a decrease in his working capacity and deterioration of health. This shows that a person cannot survive in a space where this amazing mixture of gases is not.
All information and facts about the atmosphere onlyconfirm its importance to people. Due to its presence, the opportunity to develop life on Earth has appeared. Already today, having assessed the scale of the harm that humanity is capable of inflicting on life-giving air with its actions, we should think about further measures to preserve and restore the atmosphere.